D. Rut/edge, P. Bown: New names for old...... , p. 53 - 59.

Journal of Nannoplankton Research, 18, 2, 1996.

NEW NAMES FOR OLD: TAXONOMIC CLARIFICATION OF
SOME EARLY CRETACEOUS NANNOFOSSIL MARKER- SPECIESDavid Rut/edge, Robertson Research International, L/andudno, Gwynedd LL30 JSA, UK &Paul Bown, Department of Geological Sciences, University College London, Gower Street, London WCJ E 6BT, UK

Abstract: Five new boreal Early Cretaceous calcareous nannofossil species are described and illustrated:
Clepsilithus maculosus, N annoconus inornatus, Nannoconus pseudoseptentrionalis, Rhagodiscus
gallagheri and Rucinolithus windleyae. All five species have previously been misnamed or included within
the concepts of other species. The more precise taxonomic concepts introduced here provide improved
constraints for important marker-species events. One new combination, Zeugrhabdotus scutula, isintroduced.

Introduction
A detailed study of calcareous nannofossils from the boreal
area has shown that a number ofbiostratigraphically important taxa require more-precise definition. This paper
describes five new species that previous workers havegrouped with widely used marker-species, resulting in extended ranges and reduced biostratigraphical potential.
Recognition of these new taxa enables clarification of anumber ofbiostratigraphical ambiguities.
These observations are based on the detailed
biostratigraphical study of nine sections of Ryazanian toAptian age: three outcrop sections (two in England and acomposite German section) and six cores (two from onshore England, one from the southern North Sea, one from
offshore mid-Norway, and two from the Barents Sea). Allof the outcrop material and some of the core material isaccurately dated by means of cephalopods. The comprehensive results of this study will be presented in Rutledge& Bown (in prep.).
Systematic Palaeontology
Unless otherwise stated, all type-material is deposited in
the Postgraduate Unit ofMicropalaeontology, University
College London.
Genus CLEPSILITHUS Crux, 1987
Type species: Clepsilithus polystreptus Crux, 1987
Clepsilithus macu/osus sp. nov.

Plate l,Figures4-7
1982
1987
1988
1989
1991
1991

Stradnerlithus comptus Black, 1971; Taylor, p.71, pl.4.6,
figs 13-14 (EM).
Stradnerlithus comptus Black, 1971; Jakubowsk.i, p.117,
pl.2, figs 23-24 (LM).
Thurmanolithion clatratum GrOn & Zweili, 1980;
Applegate & Bergen, p.336, pl.17, fig.2 (EM).
Stradnerlithus comptus Black, 1971; Crux, p.207, pl.8.13,
figs 26-28 (LM).
Stradnerlithus comptus Black, 1971; Mutterlose (notillustrated).
Stradnerlithus comptus Black, 1971; Bralower, p.430,
fig.6.41-42 (LM).

platform; in crossed-polars the bars appear as a cycle ofregularly-spaced bright spots.
Description: The slightly flaring outer rim-cycle consists
ofabout 25 dextrally-imbricate elements, and is only weakly
birefringent (grey). The arrangement of elements in the
inner rim-cycle is uncertain, but this cycle is highly
birefringent (white) in crossed-polars. Each of the 12-16
regularly-arranged, radial bars consists of two laterallyfused elements, and exhibits white birefringence; these bars
support a rather less-birefringent (grey-white), diamondshaped platform that lies along the long axis of the central
area. There is no distal process.
Dimensions: Length 4.0-5.1J.UO, width 3.0-3.6).llll.
Remarks: This Upper Hauterivian marker species has beenpreviously misnamed Stradnerlithus comptus (e.g.
Jakubowski, 1987; Crux, 1989). S. comptuswasoriginallydescribed from the Kimmeridgian by Black (1971, pl.31,
fig.1 0) and has a similar number of radially-arranged bars,
but these are more delicately constructed and support aslender longitudinal bar, not a diamond-shaped platform.
However, the most significant difference between the two
species is their rim structure: S. comptus has a narrow,monocyclic-appearing rim composed of non-imbricate elements. In the light-microscope, the two are easily distinguished, S. comptus being weakly birefringent and inconspicuous, while C. macu/osus has a highly birefringent inner rim-cycle and central-area bars.
C/epsilithus polystreptus differs from C. maculosus
in having a less-developed inner rim-cycle, and fewer central bars (that are differently constructed), but this small
form has not yet been observed in the light-microscope.
The only contemporary species with which C. maculosus
might be confused is the similarly proportioned
Cretarhabdus inaequalis, but the latter species has a lessregular central structure.
Derivation of name: Latin, macu/osus meaning spotted,
referring to the brightly-spotted appearance of the cycleof central-area bars in crossed-polars.

Diagnosis: Small (4.0-5.0j.Ull), elliptical murolith with a bicyclic rim, the outer cycle of which is dextrally imbricate,

Holotype: Pl.l, fig.4 (EM).

and a central area occupied by about 14 short, radiallyarranged bars which support a diamond-shaped central

Paratype: PI. I, fig.6 (LM).

========================~53==========================

Journal of Nannoplankton Research, 18, 2, 1996.

Type locality & level: BGS Borehole 81/43 (southern NorthSea), 32.80m (Upper Hauterivian).

D. Rut/edge, P. Bown: New names for old ...... , p. 53 -59.

Holotype: Pl.l, fig.8 (EM).
Paratype: Pl.l, fig.9 (EM); Pl.l, fig.l6 (LM).

Occurrence: Hauterivian of the North Sea area,
occurringconsistently within the uppermost Hauterivian(above the last occurrence of Tegulalithus septentrionalis). The last occurrence of this species (basal
variabilis Amm. Zone) provides an excellent approximationof the Hauterivian-Barremian boundary, as currently defined at Speeton.
Genus NANNOCONUS Kamptner, 1931
Type species: Nannoconus steinmannii Kamptner,
1931
Nannoconus inornatus sp. nov.

Plate 1,Figures 8-12, 14-18
1982
1987

Nannoconus abundans Stradner & Griln, 1973; Taylor
pl.4.6, fig.19 (EM).
Nannoconus abundans Stradner & Griin, 1973; Thoms~n,pl.6, figs 10-11 (EM).

Diagnosis: A short, biconcave, pillar-like nannoconid constructed from thin plates arranged in a very low-angled
spiral, with a narrow axial canal.
Description: The sides of this nannoconid are convex, andthe ends unflared, slightly concave and identical, thus
apical/basal ends cannot be distinguished. The height isgenerally less than the diameter, often considerably less.
The axial canal is very much narrower than the wall of thenannoconid. The outer surface of the wall is smooth, giving a circular profile in end view. The thin plates composing the wall are arranged in a very low-angled spiral.
Dimensions: Diameter 5.0-9.01!ffi. height2.5-6.0Jllll
Remarks: Several previous authors (e.g. Taylor, 1982;
Thomsen, 1987) have included Nannoconus inornatus
within their concept of Nannoconus abundans, and consequently recorded an anomalously early first occurrence
for this marker-species. N. inornatus is considered to be
the ancestor ofN. abundans, but it is important to differentiate between the two species clearly, in order to maintainthe biostratigraphical integrity ofN. abundans.
N. inornatus differs from N. abundans in lacking a?basal flange, from Nannoconus circularis, Nannoconus
globulus and Nannoconus inconspicuus in having a narrower central canal, and from Nannoconus ligius in its
non-petalloid profile.
Two varieties of this species were recorded: a larger,
highly birefringent form, and a smaller, shorter variety yielding only white birefringence in end view. N. inornatus
developed vertical ribs in the Early Barremian (latefissicostatum Amm. Zone), giving it a regularly scalloped
margin in end view. These ribbed forms probably gave rise
to Nannoconus pseudoseptentrionalis sp. nov. in the late
Early Barremian (elegans Amm. Zone).
Derivation of name: Latin, inornatus meaning unadorned,
referring to the simple, un:flanged form of this species.

Type locality & level: BGS Borehole 81/43 (southern NorthSea); 14. 70m (Lower Barremian).
Occurrence: Upper Hauterivian-Barremian of the North
Sea area; rare through the lower part of this range, but
becoming common/abundant in the Lower Barremian,justprior to the inception of N. abundans.
Nannoconus pseudoseptentrionalis sp. nov.

Plate 1, Figures20-22?1987 Nannoconus quadriangulus quadriangulus Deflandre &Deflandre-Rigaud, 1967; Thomsen, pl.6, figs 6, 7, 9 (EM).
1989 Tegulalithus septentrionalis (Stradner, 1963) Crux, 1986;
Crux, p1.8.9, figs 5, 6 (EM).

Diagnosis: A short, flangeless nannoconid with a very
narrow axial canal, and an irregular, ragged margin, as seen
in end/plan view.
Description: This speCies is so short that it has only been
seen in end/plan view. The thin, shallowly-spiralling plates
composing the test overlap irregularly to give a ragged
margin. This form lacks regularly-spaced vertical ribs, andthus its margin is not regularly scalloped. The axial canal ismuch narrower than the width of the wall. It is highly
birefringent in the light-microscope.
Dimensions: Diameter: 4.5-7.0Jllll
Remarks: N. pseudoseptentriona/is is differentiated fromother similar nannoconids by its irregular, ragged margin.
This renders it similar to Tegula/ithus septentrionalis incrossed-polars, and it has been identified as such in several
previous studies (e.g. Crux, 1989). These optically-similar
species are readily differentiated in phase-contrast (in which
T. septentrionalis displays regularly-spaced wall elements)
and in side view (T. septentriona/is is commonly encountered in highly-distinctive side view). In end view, N.
pseudoseptentriona/is lacks the weakly birefringent flanges
often (but not always) seen on T. septentriona/is (see Pl.l,
fig.23).
Derivation of name: Greek, pseudes meaning fulse, i.e. falseseptentrionalis.
Holotype: Pl.1, :fig.20 (LM).
Paratypes: Crux(l989), p.l99,pl.8.9,:fig.5 (EM); Crux(1989),
p.199,pl.8.9,:fig.6(EM)(OttoGott, Germany, Bed 109, 'Middle' Barrernian, Aulacoteuthis Belemnite Zone).
Type locality & level: Speeton, NE England, Speeton Clay
Formation,LowerCementBed49,LowerBarrernian,elegans
Amm.Zone.
Occurrence: 'Middle' Barremian of the North Sea area.
This species is common in the Lower Cement Beds of

54==========================

D. Rut/edge, P. Bown: New names for old...... , p. 53 - 59.

Speeton (elegans Amm. Zone) and at a corresponding level in Germany. It is associated with common/abundant
Zeugrhabdotus scutula nov. comb. at both localities.

Journal of Nannoplankton Research, 18, 2, 1996.

GenusRUCJNOLITHUSStover, 1966
Type species: Rucinolithus hayi Stover, 1966
Rucino/ithus wind/eyae sp. nov.

Genus RHAGODJSCUS Reinhardt, 1967
Type species: Discolithus asper Stradner, 1963,
designated by Reinhardt, 1967
Rhagodiscus gallagheri sp. nov.

Plate I, Figures l-3
1987

Rhagodiscus angustus (Stradner, 1963) Reinhardt, 1971 ;Thomsen, p.77, pl.l6, figs 6-8 (EM).

Diagnosis: Small (<5 .OIJ.Illlong), eliipticalRhagodiscus witha length/width ratio of <2.5, and straight or slightly convex
longer sides. The central area is filled with a proximallysituated granular plate and spanned by short, transverse
struts which support a relatively large, hollow spine-base.
Dimensions: Length 3.5-4.5j.Ull.
Remarks: Previously included within the species conceptof Rhagodiscus angustus by several authors (Thomsen,
1987; Mutterlose, 1991), Rhagodiscus gallagheri occurs
earlier than Rhagodiscus angustus and is distinguished byits smaller size and more-elliptical outline. Morphologies
transitional between these two species have been observed,
confirming the difficulty in using R. angustus as a zonal
marker. Note that Stradner's (1963) holotype drawing of
Rhagodiscus angustus is parallel-sided with dimensions
5.0J.lm x 2.0J.lm. The oldest forms with these dimensions
were recorded, in our study, from the Chale Clay, Isle ofWight, from the lower forbesi Amm. Zone (intra-Lower
Aptian), although R. gal/agheri is still the dominant form
at this level. This first occurrence for R. angustus is still
very much earlier than the basal Upper Aptian event recorded by previous authors, perhaps reflecting application of an even narrower species concept, i.e. very elongate forms with a length/width ratio of> 3.
Derivation of name: Named inhonourofDr. Liam Gallagher,

nannopalaeontologist.
Holotype: Pl.1, fig.1 (LM).
Paratype: Thomsen (1987), p.77, pl.l6, fig.6 (EM) (Well
E-1, Danish Sector of the North Sea, 8193', basal Aptian).
Reproduced here as PI. I, fig.3.
Type locality & level: Atherfield Point (Isle of Wight),
Atherfield Clay Formation (Sample AC 13), Lower Aptian,forbesi Amm. Zone.
Occurrence: Common throughout the Aptian of the North
Sea area; particularly abundant in nannofossiliferous sampies from the Atherfield Clay, Isle ofWight, southern England (fissicostatus-forbesi Amm. Zones).

===========================55Plate I, Figures 24-29? 1987 Lithastrinus sp. Bralower, p.298 (not illustrated).

Diagnosis: Nannolith consisting of two inclined cycles ofbroad, petal-like elements: a wider ?proximal cycle of aboutnine regularly-imbricate elements, and a ?distal cycle formed
from a lesser nUf!lber of irregularly-overlapping elements.
Description: Two inclined cycles ofbroad, petal-like elements join at the solid centre of the nannolith; there is nocentral-area diaphragm structure. The wider ?proximal cycle consists of about nine sinistrally-imbricate, broadlypetalloid elements. The ?distal cycle consists of a lesser
number of irregularly-arranged elements, at least one ofwhich projects distally, overlapping the other elements ofthis cycle. In proximal view in the light-microscope, thisform appears as a large (7. 0-11.0 J.Lm), highly- birefringent
rosette, with imbricating, petalloid elements; distal focusing reveals the irregular distal cycle. In side view, it exhibitsa typical polycyclolith construction (sensu Varol, 1992),
with two cycles of inclined elements. The fairly high andirregular form of this species ensure that it is often encountered in oblique view in the light-microscope, where it appears as an irregular, radiating birefringent body.
Dimensions: Diameter 7.8-11.0j.Lill.
Remarks: This species is only tentatively assigned to ·Rucinolithus, due to its bicyclic construction. It would
seem to be intermediate between previously described species of Rucinolithus (mostly older) and fully formed
polycyclolithaceans, in which the two cycles of thenannolith are equally developed.
Differentiation: R. windleyae differs fromLithastrinus (asemended by Varol, 1992) in lacking a small central diaphragm. It is similar and possibly related to Rucino/ithus
pinnatus Bergen, 1994, but this older species (middle
Tithonian to latest Berriasian) has only eight imbricate elements and lacks a well-developed, irregular ?distal cycle,
having instead, a small-element cycle surrounding a central perforation. R windleyae is differentiated from the lightmicroscopically similar Assipetra terebrodentarius (PI. I,
figs 30, 31) by its larger size, and petalloid, rather than globular, habit. It is impOrtant to make this distinction in order toretain the biostratigraphical integrity of the latter species,
which has a first occurrence in the uppermost Hauterivian.
Derivation ofname: Named in honour of Dr. Dawn E.
Windley, erstwhile nannopalaeontologist.
Holotype: Pl.1, fig.25 (EM).
Paratype: Pl.l, fig.27 (EM); Pl.1, fig.28 (LM).

Journal of Nannoplankton Research, 18, 2, 1996.

D. Rutledge, P. Bown: New names for old......, p. 53 - 59.

Type locality & level: BGS Borehole 81/43 (southern NorthSea), 4l.l6m (Upper Hauterivian).

Occurrence: Lower/Upper Hauterivian boundary to Lower
Barremian ofBGS Borehole 81/43 and the Speeton section;rare through most of this range, but occasionally common
in the Upper Hauterivian to basal Barremian. Bralower (1987)
recorded the first occurrence of 'Lithastrinus sp.' (which
included the later-appearingAssipetra terebrodentarius)
in the Upper Hauterivian of a number of tethyan sites.
Genus ZEUGRHABDOTUS Reinhardt, 1965
Type species: Zygolithus erectus Dejlandre in
Dejlandre & Fert, 1954, designated by Reinhardt,

1965
Zeugrhabdotus scutula (Bergen, 1994) comb. nov.
Basionym: Reinhardites scutula Bergen, 1994 (Journal of
Nannoplankton Research, 16(2): 59-69, p.64, pl.l, figs
24a-c (holotype ), 25a-b ).
1989
1994

Zeugrhabdotus sisyphus (Gartner, 1968) Crux, p.198,
pl.8.7, fig.l (EM); pl.8. 12, fig.30 (LM).
Reinhardites scutula Bergen, 1994, p.64, pl.l, figs 24a-c(holotype), 25a-b (EM and LM; same specimen).

Remarks: Previous authors have assigned this species to
Zeugrhabdotus sisyphus, but included several other species (e.g. Z. trivectis) in this category, giving a much longer,

composite range. We believe that this species is best classified within the genus Zeugrhabdotus although it may
well be the ancestral species to the Reinhardtites lineageof the Late Cretaceous, as suggested by Bergen ( 1994).
Acknowledgements
We would like to thank DENI for funding of this research
project, IKU and BGS for the provision of sample materialand stratigraphic information, and Tim Bralower, Jim Bergen,
Osman Varol and Peter Rawson for advice, discussion andhelp along the way.
RERERENCES
Black, M. 1971. Coccoliths of the Speeton Clay and Sutterby
Mar!. Proceedings of the Yorkshire Geological Society,38(3): 381-424.
Bergen, J.A. 1994 . Berriasian to Early Aptian calcareous
nannofossils from the Vocontian Trough (S.E. France)and deep sea drilling site 534: new nannofossil taxa and asummary oflow-latitude biostratigraphic events. JournalofNannoplankton Research, 16(2): 59-69.
Bralower, T.J. 1987. Valanginian toAptiancalcareousnannofossil
stratigraphy and correlation with the upper M-sequencemagnetic anomalies. Marine Micropaleontology, 11: 293310.
Crux, J.A. 1987. Six new species of calcareous nannofossils fromthe Lower Cretaceous strata of England and Germany.
INA Newsletter, 9: 30-35.

Crux, J .A. 1989. Biostratigraphy and palaeogeographical applications of Lower Cretaceous nannofossils from northwestern Europe: 143-211. In: J.A. Crux & S.E. van Heck
(Eds). Nannofossils and their Applications. British
Micropalaeontological Society Series, Ellis Horwood Ltd.,
Chichester.
Jakubowski, M. 1987. A proposed Lower Cretaceous calcareous nannofossil zonation scheme for the Moray Firtharea of the North Sea. Abhandlungen Geologischen
Bundesanstalt, 39: 99-119.
Mutterlose, J. 1991. Das Verteilungs- und Migrationsmuster deskalkigen Nannoplanktons in der borealen Unterkreide(Valangin-Apt) NW-Deutschlands. Palaeontographica,
B221: 27-152.
Rutledge, D. & Bown, P.R. (in prep.). Calcareous nannofossilsof the boreal Lower Cretaceous.
Stradner, H. 1963. New contributions to Mesozoic stratigraphy
by means of nannofossils. Proc. 6th World Petroleum
Congress Frankfurt, Sect.]: 167-182.
Taylor, R.J. 1982. Lower Cretaceous (Ryazanian to Albian)calcareous nannofossils: 40-80. In: A.R. Lord (Ed.). A
Stratigraphical Index of Calcareous Nannofossils.
British Micropalaeontological Society Series, Ellis
Horwood Ltd., Chichester.
Thomsen, E. 1987. Lower Cretaceous calcareous nannofossil
biostratigraphy in the Danish Central Trough. Danmarks
Geologiske Undersegelse, Series A, 20: 1-89.
Varol, 0. 1992. Taxonomic revision of the Polycyclolithaceae
and its contribution to Cretaceous biostratigraphy. Newsletters on Stratigraphy, 27(3): 93-127.

List of species cited in the text
Assipetra terebrodentarius (Applegate et al., 1987 in
Covington& Wise, 1987) Rutledge & Bergen in
Bergen, 1994
Clepsilithus maculosus sp. nov.
Clepsilithus polystreptus Crux, 1987
Cretarhabdus inaequalis Crux, 1987
Nannoconus abundans Stradner & Griin, 1973
Nannoconus circularis Deres and Acheriteguy, 1980
Nannoconus globulus Bronnimann, 1955
Nannoconus inconspicuus Deflandre in Deflandre &Deflandre-Rigaud, 1962
Nannoconus inomatus sp. nov.
Nannoconus pseudoseptentrionalis sp. nov.
Nannoconus ligius Applegate & Bergen, 1988
Rhagodiscus angustus (Stradner, 1963) Reinhardt, 1971
Rhagodiscus gallagheri sp. nov.
Rucinolithus windleyae sp. nov.
Stradnerlithus comptus Black, 1971
Tegulalithus septentrionalis (Stradner, 1963) Crux, 1986
Zeugrhabdotus scutula nov. comb. (= Zeugrhabdotus
sisyphus Burnett in Gale et al. in press)

56========================~

D. Rut/edge, P. Bown: New names for old...... , p. .53 - .59.

Journal of Nannoplankton Research, 18, 2, 1996.

57

Journal of Nannoplankton Research, 18, 2, 1996.

D. Rut/edge, P. Bown: New names for old......, p. 53 - 59.

PLATE 1
Light micrographs x2112 magnification; electron micrographs, magnification as stated. Negatives are stored in the Postgraduate Unit ofMicropalaeontology, University College London. Neg.- negative number; LM- light-micrograph; SEM- scanning electron micrograph; xp - crossed-polars; pc - phase-contrast.
Figs 1-3:
Figs 1, 2:
Fig.1:
Fig.2:
Fig.3:

Rhagodiscus gal/agheri sp. nov.
Atherfield Clay Formation (Isle of Wight), AC 13, Lower Aptian, forbesi Amm. Zone.
Holotype, LM-xp,- Neg.5051-9.
LM-xp, Neg.5051-8.
Paratype, from Thomsen, 1987, p.77, pl.16, fig.6; Well El, 8193', Lower Aptian.

Figs 4-7:

Clepsi/ithus maculosus sp. nov.
BGS Borehole 81/43 (southern North Sea), 32.80m, Upper Hauterivian.
Holotype, SEM, distal view, x9180, Neg.4061-11.
SEM, distal oblique view, x8500, SEM, Neg.4061-12, same specimen as Fig.4.
Paratype, LM-xp, Neg.4071-19.
LM-pc, Neg.4071-21 , same specimen as Fig.6.

Fig.4:
Fig.5:
Fig.6:
Fig.7:

Figs 8-12, 14-18: Nannoconus inornatus sp. nov.

Figs 8-12:
Fig.8:
Fig.9:
Fig.10:Fig.ll:Fig.12:
Fig.14:
Fig.15:
Fig.16:
Fig.17:
Fig.18:BGS Borehole 81/43 (southern North Sea), 14.70m, Lower Barremian.
Holotype, SEM, oblique view, x5000, Neg.4079-17.
Paratype, SEM, oblique view, x5250, Neg.4079-16.
SEM, oblique view, x4875, Neg.4079-24.
SEM, oblique view, x5000, Neg.4079-22.
SEM, end view ofFig.11, x5000, Neg.4079-21.
LM-xp, side and end views, 'Neg.4099-6, Speeton, Bed LBSC.ID, Lower Barremian, rarocinctum Amm. Zone.
LM-pc, Neg.4099-7, same' specimens as Fig.l4.
Paratype, LM-xp, Neg.4099-4, side view, Speeton, Bed LBSC.ID, Lower Barremian, rarocinctum Amm. Zone.
LM-xp, Neg.3545-28, end view, Speeton, Bed LB1F (10), Lower Barremian, fissicostatum Amm. Zone.
LM-pc, Neg.3723-11, end view, Speeton, Bed LB5C.ID, Lower Barremian, rarocinctum.Amm. Zone.

Figs 13, 19:

Nannoconus abundans Stradner & Giiln, 1973.
Speeton, Bed LB1F (13), Lower Barremian, fissicostatum Amm. Zone.
SEM, oblique view, x4000, Neg.4069-29.
LM-xp, side view, Neg.3545-4.

Fig.13:
Fig.19:Figs 20-22:
Fig.20:
Fig.21:
Fig.22:

Nannoconus pseudoseptentrionalis sp. nov.
Speeton, Lower Cement Bed 49, Lower Barremian, elegans Amm. Zone.
Holotype, LM-xp, end view, Neg.4094-20.
LM-pc, Neg.4094-21, same specimen as Fig.20.
LM-xp, end view, Neg.4065-32.

Fig.23:Tegulalithus septentrionalis (Stradner, 1963) Crux, 1986.
LM-xp, Neg.4023-27, side and end views, BGS Borehole 81/43 (southern North Sea), 41.16m, Upper Hauterivian.

Figs 24-29:
Fig.24:
Fig.25:Fig.26:
Fig.27:
Fig.l8;
Fig.29:Rucinolithus windleyae sp. nov.
BGS Borehole 81143 (southern North Sea), 41.16m, Upper Hauterivian.
SEM, oblique view, x3875, Neg.4063-28.
Holotype, SEM, same specimen as Fig.24, x4000, Neg.4063-29.
SEM, ?distal view, x4000, Neg.4063-31 .
Paratype, SEM, side view, x4500, Neg.4060-30.
Paratype, LM-xp, Neg.4023-32.
LM-xp, Neg.4023-24.

Figs 30,31:
Fig.30:
Fig.31:

Assipetra terebrodentarius (Applegate et al., 1987 in Covington & Wise, 1987) Rutledge & Bergen in Bergen, 1994
LM-xp, Neg.4071-17, BGS Borehole 81/43 (southern North Sea), 11.92m, Lower Barrremian.
LM-pc, Neg.4071-18, same specimen as Fig.30.

Figs 32,33:
Fig.32:
Fig.33:

Assipetra infracretacea (Thierstein, 1973) Roth, 1973.
LM-xp, Neg.4071-2, BGS Borehole 81/43 (southern North Sea), 62.38m, Lower Hauterivian.
LM-pc, Neg.4071-3, same specimen as Fig.32.

========================~58

D. Rutledge, P. Bown:ew names for old. ..... , p. 53 - 59.

Journal of Nannoplanklon Research, 18, 2, 1996.

PlATE 159======================~